Radian Aerospace will test the Radian One spaceplane model this year

Livingston Holder, who was the X-33 program manager for NASA, is the company’s chief technology officer and is overseeing the new effort.

Holder told CNN that enough has changed since 2001 to make creating a space plane a more realistic goal.

“We have composite materials that are lighter, tougher and can handle a greater thermal range than we had then,” he said. “And the propulsion is better than anything we’ve had, in terms of how efficiently the propellant burns and how much the systems weigh.”

The company has raised nearly $28 million to build Radian One in 2022 and told CNN it plans to test a scale model this year.

Why we need space planes

Demand for launching things into space—like satellites, which make everything from weather forecasting to GPS possible—is only growing.

Rockets remain the best option for doing that, even if they are “terribly inefficient and expensive,” according to NASA.

A typical rocket consists of several stages that are expensive to build and often discarded after a single use.

Companies like SpaceX have revolutionized rocket technology and driven down costs with fleets of reusable rockets like the Falcon 9.

But spaceplanes, requiring less fuel and no rocket stages, could provide another cheap and more comfortable alternative to space travel.

How Radian One could provide cheap and comfortable space travel

Unlike a rocket, which launches vertically, the Radian One concept uses a rocket-propelled sled.

The sled would carry the plane along a two-mile-long track, accelerating it to a speed of 537 miles per hour and then launching it into space.

The plane would then fly the rest of the way on its own engines. Using the sled to reach launch speed reduces the amount of fuel the spacecraft itself must carry, according to Radian’s website.

This airline-like rise would make for a more comfortable ride for passengers, according to Radian. The company also hopes it could lower the cost of spaceflight.

It’s not clear by how much, but for an idea, NASA hoped its X-33 space plane would reduce the cost of sending a pound of payload into orbit from $10,000 to $1,000.

The Radian One wouldn’t be a replacement for all rockets, though.

Radian’s space plane would be able to carry smaller payloads into space, making it the equivalent of a pickup truck, he told CNN. Traditional rockets, Holder said, will likely stick around for heavier payloads, making them the 18-wheelers of this analogy.

A full-sized plane won’t take to the skies until 2028, and even then, the company doesn’t expect to reach orbit yet. But if successful, the Radian One could finally present a low-cost option for a growing segment of space travel.